Popcorn of the type commonly known as “kettle corn” is popped in a large metal kettle which is heated by an open flame. Tiresome stirring of the popping popcorn is required to provide even heat distribution to the popcorn and prevent burning. This method of popping popcorn dates back to colonial times and is considered to produce popcorn with enhanced flavor and texture. Kettle corn is made and sold primarily at outdoor locations such as fairs, festivals, and flea markets where the open flame is created by burners using liquid propane for fuel which are able to quickly flash heat the kettle to temperatures sufficient to pop the popcorn. The liquid propane is stored under pressure in tanks. Liquid propane, being under pressure, supplies sufficient fuel to the burner which enables the burner to heat the kettle to temperatures required to pop the popcorn.
Making kettle corn at indoor locations, such as malls, presents particular problems. There are regulations for both building and fire codes that prohibit use of pressurized propane tanks at indoor locations. Use of natural gas, piped in through gas lines, is required. The natural gas is maintained at relatively low pressure as a safety precaution. This low pressure helps minimize the amount of natural gas that may escape through leaks in the gas lines and any devices or equipment that use the low pressure natural gas. Additives are used with odorless natural gas to give it a “rotten-egg” odor so that leaks may be more easily detected. This relatively low pressure, under which the natural gas is held, causes an insufficient supply of natural gas delivered to the burner to create high enough temperatures to flash heat the kettle to pop the popcorn.